Screening effect on the binding energies of shallow donors, acceptors and excitons in finite-barrier quantum wells

Akbas H., Aktas S., Okan S., Ulas M., Tomak M.

SUPERLATTICES AND MICROSTRUCTURES, vol.23, no.1, pp.113-119, 1998 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 23 Issue: 1
  • Publication Date: 1998
  • Doi Number: 10.1006/spmi.1996.9993
  • Journal Name: SUPERLATTICES AND MICROSTRUCTURES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.113-119
  • Middle East Technical University Affiliated: Yes

Abstract

The conduction and valence subband energies in the presence of an electric field are calculated using the fifth-order Runge-Kutta method. The binding energies of shallow donors, accepters and excitons in finite-barrier GaAs/Ga1-xAlx As quantum wells are then obtained variationally in the presence of a magnetic field. The effects of a spatially dependent screening function epsilon(r) On the calculation of binding energies are specifically investigated. The use of epsilon(r) in comparison with the use of a constant epsilon(0) increases the binding energy of accepters as the increase on shallow donors and excitons is quite small. (C) 1998 Academic Press Limited.